Macro Split Calculator
Determine your optimal daily protein, carbohydrate, and fat targets in grams and calories based on your body weight, fitness goal, and training intensity. Supports cutting, bulking, maintenance, and ketogenic splits.
About this calculator
Macronutrient targets are derived from body weight multiplied by goal-specific and activity-adjusted protein multipliers, since protein is the most critical variable for body composition. Protein calories = Math.round(protein_g × 4), where protein_g = weight × multiplier. For a keto goal the multiplier is 1.6 g/kg; for a cut it ranges from 2.0–2.2 g/kg depending on training intensity; for a bulk it is 2.2–2.4 g/kg. Each gram of protein and carbohydrate provides 4 kcal, while each gram of fat provides 9 kcal. Once protein calories are fixed, remaining daily calories are distributed between fat and carbohydrates according to the goal split — keto allocates roughly 70–75% of remaining calories to fat, while standard cut and bulk splits favour carbohydrates as the primary fuel for training performance.
How to use
Example: 80 kg male, bulking goal, high training intensity. Step 1 — Protein multiplier for bulk + high activity: 2.4 g/kg. Step 2 — Protein target: 80 × 2.4 = 192 g/day. Step 3 — Protein calories: 192 × 4 = 768 kcal. Step 4 — If daily calorie target is 3,200 kcal, remaining calories = 3,200 − 768 = 2,432 kcal. Step 5 — A standard bulk splits remaining calories roughly 60% carbs / 40% fat: carbs = (2,432 × 0.6) ÷ 4 ≈ 365 g; fat = (2,432 × 0.4) ÷ 9 ≈ 108 g. Enter your values and the calculator performs these steps automatically.
Frequently asked questions
How much protein per kilogram of body weight do I really need to build muscle?
The current scientific consensus, reflected in position statements from the International Society of Sports Nutrition, recommends 1.6–2.2 g of protein per kg of body weight per day for individuals engaged in resistance training who want to maximise muscle protein synthesis. Higher intakes (up to 3.1 g/kg) during aggressive caloric deficits can help preserve lean mass but offer diminishing returns in a caloric surplus. Spreading protein intake across 3–5 meals of roughly 20–40 g each appears to maximise muscle protein synthesis compared to consuming most protein in a single meal.
What is the best macro split for fat loss while preserving muscle mass?
Research supports a high-protein, moderate-carbohydrate approach for fat loss: approximately 30–35% of calories from protein, 35–40% from carbohydrates, and 25–30% from fat. The exact split matters less than two non-negotiable anchors: adequate protein (≥1.6 g/kg body weight) to prevent muscle loss, and a consistent calorie deficit. Carbohydrates should be prioritised around training sessions to fuel performance, while dietary fat should remain above ~0.8 g/kg to support hormonal health, particularly testosterone production.
How does a ketogenic macro split differ from a standard cutting diet in terms of carbohydrate intake?
A standard cutting diet typically keeps carbohydrates at 35–45% of total calories — often 200–350 g/day for most active individuals — to fuel high-intensity training and maintain glycogen stores. A ketogenic diet restricts carbohydrates to under 50 g/day (roughly 5–10% of calories) to induce ketosis, a metabolic state in which the liver produces ketone bodies from fat as the primary fuel source. The practical trade-off is that ketogenic dieters often experience reduced high-intensity performance due to limited glycolytic fuel, making keto more suited to lower-intensity or endurance activities than to heavy resistance training or sprint-based sports.